Operating instructions

24
Maintenance
PROBLEM POSSIBLE CAUSE
SOLUTION
LOW
WATER
TEMPERATURE
Improper fuel or water in fuel Replace with clean and proper fuel.
Low fuel pressure Increase fuel pressure.
Weak fuel pump
Check fuel pump pressure. Replace pump if
needed.
Fuel filter partially clogged Replace as needed.
Soot build-up on coils not allowing
heat transfer
Clean coils.
Improper burner nozzle See specifications.
WATER
TEMPERATURE
TOO HOT
Incoming water to machine warm or
hot
Lower incoming water temperature.
Fuel pump pressure too high See specifications for proper fuel pressure.
Fuel pump defective Replace fuel pump.
Detergent line sucking air
Tighten all clamps. Check detergent
lines for holes.
Defective temperature switch Replace.
Incorrect fuel nozzle size See specifications for proper fuel nozzle.
Insufficient water supplied Check water G.P.M. to machine.
Restricted water flow Check nozzle for obstruction, proper size.
PUMP
NOISY
Air in suction line
Check water supply and connections on
suction line.
Broken or weak inlet or discharge
valve springs
Check and replace if necessary.
Excessive matter in valves Check and clean if necessary.
Worn bearings Check and replace if necessary.
PRESENCE
OF WATER
IN OIL
Oil seal worn Check and replace if necessary.
High humidity in air Check and change oil twice as often.
WATER
DRIPPING
FROM
UNDER PUMP
Piston packing worn Check and replace if necessary.
O-Ring plunger retainer worn Check and replace if necessary.
Cracked piston Check and replace if necessary.
Pump protector
Lower water supply pressure. Do not run
with spray gun closed longer than 2 minutes
Karcher HDS 600-612 Operator’s Manual 9.800-080.0 - BH